<template>
    <div class="shopcart">
        <div class="content" @click="toggleList">
            <div class="content-left">
                <div class="logo-wrapper">
                    <div class="logo" :class="{'highlight':totalCount>0}">
                        <i class="icon-shopping_cart" :class="{'highlight':totalCount>0}"></i>
                    </div>
                    <div class="num" v-show="totalCount>0">{{totalCount}}</div>
                </div>
                <div class="price" :class="{'highlight':totalPrice>0}">¥{{totalPrice}}</div>
                <div class="desc">另需配送费¥{{deliveryPrice}}元</div>
            </div>
            <div class="content-right">
                <div class="pay" :class="payClass" @click.stop.prevent="pay">{{payDesc}}</div>
            </div>
        </div>
        <div class="ball-container">
            <div v-for="(ball,index) in balls" :key="index">
                <transition name="drop" @before-enter="beforeDrop" @enter="dropping" @after-enter="afterDrop">
                    <div class="ball" v-show="ball.show">
                        <div class="inner inner-hook"></div>
                    </div>
                </transition>
            </div>
        </div>
        <transition name="flod">
            <div class="shopcart-list" v-show="listShow">
                <div class="list-header">
                    <div class="title">购物车</div>
                    <div class="empty" @click="empty">清空</div>
                </div>
                <div class="list-content" ref="listContent">
                    <ul>
                        <li class="food" v-for="(food,index) in selectFood" :key="index">
                            <span class="name">{{food.name}}</span>
                            <span class="price">¥{{food.price*food.count}}</span>
                            <div class="cartcontrol-wrapper">
                                <cartcontrol @add="addFood" :food="food"></cartcontrol>
                            </div>
                        </li>
                    </ul>
                </div>
            </div>
        </transition>
        <transition name="fade">
            <div class="list-mask" @click="hideList" v-show="listShow"></div>
        </transition>
    </div>
</template>

<script type="text/ecmascript-6">
import BScroll from 'better-scroll';
import cartcontrol from '../../components/cartcontrol/cartcontrol';
    export default {
        props: {
            selectFood: {
                type: Array,
                default () {
                    return [];
                }
            },
            deliveryPrice: {
                type: Number,
                default: 0
            },
            minPrice: {
                type: Number,
                default: 0
            }
        },
        data () {
            return {
                balls: [
                    {
                        show: false
                    },
                    {
                        show: false
                    },
                    {
                        show: false
                    },
                    {
                        show: false
                    },
                    {
                        show: false
                    }
                ],
                dropBalls: [],
                fold: true
            };
        },
        computed: {
            totalPrice () {
                let total = 0;
                this.selectFood.forEach((food) => {
                    total += food.price * food.count;
                });
                return total;
            },
            totalCount () {
                let count = 0;
                this.selectFood.forEach((food) => {
                    count += food.count;
                });
                return count;
            },
            payDesc () {
                if (this.totalPrice === 0) {
                    return `¥${this.minPrice}元起送`;
                } else if (this.totalPrice < this.minPrice) {
                    let diff = this.minPrice - this.totalPrice;
                    return `还差${diff}元起送`;
                } else {
                    return '去结算';
                }
            },
            payClass () {
                if (this.totalPrice < this.minPrice) {
                    return 'not-enough';
                } else {
                    return 'enough';
                }
            },
            listShow () {
                /* eslint-disable */
                if (!this.totalCount) {
                    this.fold = true;
                    return false;
                }
                let show = !this.fold;
                if (show) {
                    this.$nextTick(() => {
                        if (!this.scroll) {
                            this.scroll = new BScroll(this.$refs.listContent, {
                                click: true
                            });
                        } else {
                            this.scroll.refresh();
                        }
                    });
                }
                return show;
            }
        },
        methods: {
            drop (el) {
                for (let i = 0; i < this.balls.length; i++) {
                    let ball = this.balls[i];
                    if (!ball.show) {
                        ball.show = true;
                        ball.el = el;
                        this.dropBalls.push(ball);
                        return;
                    }
                }
            },
            beforeDrop (el) {
                let count = this.dropBalls.length;
                while (count--) {
                    let ball = this.dropBalls[count];
                    if (ball.show) {
                        let rect = ball.el.getBoundingClientRect();
                        let x = rect.left - 36;
                        let y = -(window.innerHeight - rect.top - 22);
                        el.style.display = '';
                        el.style.webkitTransform = `translate3d(0,${y}px,0)`;
                        el.style.transform = `translate3d(0,${y}px,0)`;
                        let inner = el.getElementsByClassName('inner-hook')[0];
                        inner.style.webkitTransform = `translate3d(${x}px,0,0)`;
                        inner.style.transform = `translate3d(${x}px,0,0)`;
                    }
                }
            },
            dropping (el) {
                /*eslint-disable  */
                // 重绘以后设置transiform才有用
                let rf = el.offsetHeight;
                el.style.webkitTransform = 'translate3d(0,0,0)';
                el.style.transform = 'translate3d(0,0,0)';
                let inner = el.getElementsByClassName('inner-hook')[0];
                inner.style.webkitTransform = 'translate3d(0,0,0)';
                inner.style.transform = 'translate3d(0,0,0)';
            },
            afterDrop (el) {
                let ball = this.dropBalls.shift();
                if (ball) {
                    el.style.display = 'none';
                    ball.show = false;
                }
            },
            toggleList () {
                if (!this.totalCount) {
                    return;
                }
                this.fold = !this.fold;
            },
            addFood (target) {
                this._drop(target);
            },
            _drop (target) {
                // 优化体验，异步执行
                this.$nextTick(() => {
                    this.drop(target);
                });
            },
            empty () {
                this.selectFood.forEach((food) => {
                    food.count = 0;
                });
            },
            hideList () {
                this.fold = true;
            },
            pay () {
                if (this.totalPrice < this.minPrice) {
                    return;
                }
                window.alert(`支付${this.totalPrice}元`);
            }
        },
        components: {
            cartcontrol
        }
    };
</script>

<style lang="stylus" rel="stylesheet/stylus">
@import '../../common/stylus/mixin'
.shopcart
    position :fixed
    left :0
    bottom :0
    z-index :50
    height :48px
    width :100%
    .content
        display :flex
        background :#141d27
        .content-left
            flex :1
            font-size :0
            .logo-wrapper
                display :inline-block
                position :relative
                top :-10px
                margin :0 18px
                padding-top :6px
                width :56px
                height :56px
                box-sizing :border-box
                border-radius :50%
                background :#141d27
                vertical-align :top
                .logo
                    width :44px
                    height :44px
                    margin-left :6px
                    border-radius :50%
                    background :#2b343c
                    text-align :center
                    &.highlight
                        background :rgb(0,166,220)
                    .icon-shopping_cart
                        font-size :24px
                        line-height :44px
                        color :#80858a
                        &.highlight
                            color :#fff
                .num
                    position :absolute
                    top :0
                    right :0
                    width :24px
                    height :16px
                    line-height :16px
                    text-align :center
                    border-radius :16px
                    color :#fff
                    font-size :12px
                    font-weight :700
                    background :rgb(240,20,20)
                    box-shadow :0 4px 8px 0 rgba(0,0,0,0.4)
                    &.highlight
                        font-weight :700
            .price
                display :inline-block
                line-height :24px
                font-size :12px
                font-weight :700
                color :rgba(255,255,255,0.4)
                margin :12px 0
                padding-right :12px
                box-sizing :border-box
                border-right :1px solid rgba(255,255,255,0.1)
            .desc
                display :inline-block
                vertical-align :top
                font-size :12px
                font-weight :700
                color :rgba(255,255,255,0.4)
                line-height :24px
                margin :12px 0 0 12px
        .content-right
            flex :0 0 105px
            width :105px
            text-align: center
            .pay
                height :48px
                line-height :48px
                font-size :12px
                font-weight :700
                background :#2b333b
                color :rgba(255,255,255,0.4)
                &.not-enough
                    background :#2b333b
                &.enough
                    background :#00b43c
                    color :#fff
    .ball-container       
        .ball
            position :fixed
            left :32px
            bottom :22px
            z-index :200
            transition :all 0.4s cubic-bezier(0.49, -0.29, 0.75, 0.41)
            .inner
                width :16px
                height :16px
                border-radius :50%
                background :rgb(0,160,220)
                transition :all 0.4s linear
    .shopcart-list
        position :absolute
        left :0
        top :0
        z-index :-1
        width :100%
        transform :translate3d(0,-100%,0)
        &.flod-enter, &.flod-leave-to        
            transform :translate3d(0,0,0)
        &.flod-enter-active, &.flod-leave-active
            transition :all 0.5s            
        .list-header
            width :100%
            height :40px
            background :#f3f5f7
            border-bottom :solid 1px rgba(7,17,27,0.1)
            .title
                float :left
                font-size :10px
                font-weight :200
                line-height :40px
                padding-left :18px
                color :rgb(7,17,27)
            .empty
                float :right
                font-size :10px
                color :rgb(0,160,220)
                padding-right :18px
                line-height :40px
        .list-content
            width :100%
            max-height :217px
            overflow :hidden
            background :#fff
            .food
                position :relative
                height :48px
                margin :0 16px
                border-1px(rgba(7,17,27,0.1))
                .name
                    float :left
                    font-size :14px
                    line-height :48px
                    color :rgb(7,17,27)
                .price
                    position :absolute
                    right :90px
                    top :0
                    line-height :48px
                    font-size :12px
                    font-weight :700
                    color :rgb(240,20,20)                   
                .cartcontrol-wrapper
                    position :absolute
                    top :6px
                    right :0
                    padding-left :24px
                    font-size :24px
                    line-height :48px
                    color :rgb(7,17,27)
    .list-mask
        position :fixed
        top :0
        left :0
        width :100%
        height :100%
        z-index :-10
        background :rgba(7,17,27,0.6)
        backdrop-filter :blur(10px)
        opacity :1
        &.fade-enter-active, &.fade-leave-active
            transition :all 0.5s
        &.fade-enter, &.fade-leave-to
            opacity :0
            background :rgba(7,17,27,0)
        
</style>
